Updating Client Routing Tables

When an ADDE command is run, the client checks its routing table to determine where to route the data request. If you add a remote server, you must use the DATALOC command to update the routing table on each client using the server's data.

Use one of the following methods to update the client routing tables.

Start a McIDAS session on each McIDAS-X client account and run the DATALOC commands.

Place the DATALOC commands in a text file that each client can access. Start a McIDAS session on each client and use the text file with the BATCH command to run the DATALOC commands.

Create or update a site routing table that contains the routing information for your site's clients.

The site routing table is the easiest way to modify routing tables for a large number of McIDAS-X clients. It allows the site administrator or operations staff to maintain a single table that is accessible to all clients at the site. The site routing table can be created and updated in any McIDAS-X session by using the DATALOC command to link group names to the IP addresses of remote servers. You may need to copy the table to a directory that is accessible to all clients. If a client is on another workstation, the client must NFS mount the directory to access the file.

The default file name for all client routing tables is MCTABLE.TXT. To use a different name when creating or updating the site table, you must specify the file name in the MCTABLE_WRITE environment variable value of the account running the McIDAS-X session. Write-protect the file so it can't be modified or deleted by your clients.

To make the site routing table accessible to your McIDAS-X clients, each client's MCTABLE_READ environment variable value must be modified to include this table. See Client and Server Look-up Tables for detailed information about the MCTABLE_READ and MCTABLE_WRITE environment variables.